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New Member

VG224 for incoming PSTN Analog lines

I have a stupid question for you guys. We've used VG224s internally to connect legacy Analog equipment (phones, faxes) to our IPT system.

Can you use a VG224 on the other side, to connect incoming PSTN Analog lines into the IPT system to be used to route calls inbound/outbound?


Re: VG224 for incoming PSTN Analog lines

As far as I know, you must use FXO, not FXS to connect to the PSTN.

There are FXS/DID cards that work with inbound analog DID lines, but I think those are special cards.

Too bad, eh?

A Foreign Exchange Station (FXS) interface connects directly to a standard telephone, fax machine, or similar device and supplies ring, voltage, and dial tone. The Cisco FXS interface is an RJ-11 connector that allows connections to basic telephone service equipment, keysets, and private branch exchanges (PBXes).

has some other pretty good explanations.

please rate if you find this helpful

New Member

Re: VG224 for incoming PSTN Analog lines

Thanks for the info.

We're looking at taking 35 PSTN analog ports and tying them in to our IPT system. Lacking a quick solution like a VG224 on the outside, it looks like we'll have to populate a router with a ton of FXO cards to do this.

It's a secondary solution, so I'm looking at a low cost solution. Maybe something like a 3845 with (2) 8 port HD-FXS/DID cards, each with (2) 6 port HDA-6FXO cards (total of 16 FXS ports (which I don't need) and 24 FXO Ports. Then adding (3) VWIC2-4FXO cards, and a PVDM2-48. If it would work, that would give me 36 FXO ports. I'd bump the heck out of the RAM, but other than that, do you see an easier way of getting 35 FXO PSTN lines into my IPTel config?

New Member

Re: VG224 for incoming PSTN Analog lines


i think,,,

u can apply for block of 3-40 DIDs from telecom provider, and attach it with ur PRI (sure u do have 1), 7 configure vg224 in ccm, then configure those 30-40 dids on vg224, then connect wotever u want to (fax,modem,phone)

if it helps please rate the post

New Member

Re: VG224 for incoming PSTN Analog lines

I thought of something similar. This client has a T1, but for some oddball reason, they want to migrate a bunch of independant phone lines into the front end of their IPT as failover in case their T1 PRI fails. Though we've advised against it, they are adament they want to continue to use their existing phone lines and numbers, which are not part of a continues DID block. Argh!